There are many reasons to be excited about this small vial and what it contains.

TheMayo Clinicsays anaphylaxis gets your body to release chemicals that cause you to go into shock.

Your blood pressure drops and you might have difficulty breathing.

Vial for COVID-19 vaccine

When you have anaphylaxis, you could also get a skin rash and experience nausea and vomiting.

Still, they are looking to understand how the allergic reactions took place.

Anthony Fauciare also warning those who have had Guillain-Barre syndrome against getting the COVID-19 shot.

Health care worker with COVID-19 vaccine shot

Doctors are also cautioning people with compromised immune systems against rushing to take the vaccine.

Covid-19 vaccine on a table